基于java 和 LibreOffice实现文件预览

相关链接

工具库-基于LibreOffice实现文档操作_liumapp的博客-优快云博客

LibreOffice 安装_头发浓密的程序员的博客-优快云博客

1 安装 LibreOffice

        请参考链接 

LibreOffice 安装_头发浓密的程序员的博客-优快云博客

需要记住 LibreOffice 安装主目录

2  pom 依赖

<dependency>
  <groupId>com.liumapp.workable.converter</groupId>
  <artifactId>workable-converter</artifactId>
  <version>v1.2.0</version>
</dependency>

3 配置文件 application.yml

com:
  liumapp:
    workable-converter:
      libreofficePath: "/Applications/LibreOffice.app/Contents" # LibreofficePath 安装主目录

4 controller 代码

@Controller
@RequestMapping("/viewfile")
public class ViewPdfController {
    @Autowired
    private AttachmentsService attachmentsService;

    @RequestMapping(value = "/pdf", method = RequestMethod.GET)
    @ResponseBody
    @Validated
    public void downloadFile(@RequestParam(value = "address") String address, HttpServletResponse response) throws IOException, ConvertFailedException {
        attachmentsService.libreOfficeOnlinePreview(address, response);
    }
}

 5 attachementService 代码

    public void libreOfficeOnlinePreview(String url, HttpServletResponse response) throws Exception {
        //获取文件类型
        String[] str = SmartStringUtil.split(url, "\\.");

        if (str.length == 0) {
            throw new Exception("文件格式不正确");
        }
        String suffix = str[str.length - 1];
        if (!suffix.equals("txt") && !suffix.equals("doc") && !suffix.equals("docx") && !suffix.equals("xls")
                && !suffix.equals("xlsx") && !suffix.equals("ppt") && !suffix.equals("pptx")) {
            throw new Exception("文件格式不支持预览");
        }
        PdfUtils.wordToPdf(url, response);
    }

6 PdfUtils 代码

package com.ieslab.pdfview.service.fileservice;

import com.liumapp.workable.converter.WorkableConverter;
import com.liumapp.workable.converter.core.ConvertPattern;
import com.liumapp.workable.converter.exceptions.ConvertFailedException;
import com.liumapp.workable.converter.factory.CommonConverterManager;
import com.liumapp.workable.converter.factory.ConvertPatternManager;
import org.jodconverter.document.DefaultDocumentFormatRegistry;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.util.UUID;

/**
 * @version V1.0
 * @Title:
 * @Package com.ieslab.pdfview.service.fileservice
 * @Description: TODO
 * @author: zongmoumou
 * @date 2020/10/13
 */
public class PdfUtils {
    public static void wordToPdf(String address, HttpServletResponse response) throws IOException, ConvertFailedException {
        String uuid = UUID.randomUUID().toString().replaceAll("-", "");
        String tempFilePath = "temp-" + uuid + ".pdf";
        WorkableConverter converter = new WorkableConverter();
        ConvertPattern pattern = ConvertPatternManager.getInstance();
        // 处理本地文件
        // pattern.streamToStream(new FileInputStream(address), new     FileOutputStream(tempFilePath));
        // 处理网络文件
        pattern.streamToStream(FileConvertUtil.getInputStream(address), new FileOutputStream(tempFilePath));
        pattern.setSrcFilePrefix(DefaultDocumentFormatRegistry.DOCX);
        pattern.setDestFilePrefix(DefaultDocumentFormatRegistry.PDF);
        converter.setConverterType(CommonConverterManager.getInstance());
        boolean result = converter.convert(pattern.getParameter());
        if (result) {
            outputPdf(tempFilePath, response);
            File file = new File(tempFilePath);
            if (file != null) {
                file.delete();
            }
        }
    }

    private static void outputPdf(String filePath, HttpServletResponse response) throws IOException {
        response.setHeader("Access-Control-Allow-Origin", "*");
        ServletOutputStream out = null;
        FileInputStream in = null;
        try {
            in = new FileInputStream(new File(filePath));
            String[] dir = filePath.split("/");
            String fileName = dir[dir.length - 1];
            // 设置响应类型为html，编码为utf-8，处理相应页面文本显示的乱码
            response.setContentType("application/octet-stream");
            // 设置文件头：最后一个参数是设置下载文件名
            response.setHeader("Content-disposition", "attachment;filename=" + fileName);
            out = response.getOutputStream();
            // 读取文件流
            int len = 0;
            byte[] buffer = new byte[1024 * 10];
            while ((len = in.read(buffer)) != -1) {
                out.write(buffer, 0, len);
            }
            out.flush();
        } catch (FileNotFoundException e) {

        } finally {
            response.flushBuffer();
            try {
                out.close();
                in.close();
            } catch (NullPointerException e) {

            } catch (Exception e) {

            }
        }

    }
}

7 FileConvertUtil 代码

    public static InputStream getInputStream(String filePath) throws IOException {
        // 创建URL
        filePath = getEncodeUrl(filePath).replaceAll("\\+", "%20");
        InputStream inputStream = null;
        // 创建URL
        URL url = new URL(filePath);
        // 试图连接并取得返回状态码
        URLConnection urlconn = url.openConnection();
        urlconn.connect();
        HttpURLConnection httpconn = (HttpURLConnection) urlconn;
        int httpResult = httpconn.getResponseCode();
        if (httpResult == HttpURLConnection.HTTP_OK) {
            inputStream = urlconn.getInputStream();
        }
        return inputStream;
    }